1. Field of the Invention
The present invention is an anchoring device for securement or support of articles in hard or soft materials. Many anchoring devices generally resemble "screws" as they have a spiraling thread about their lower ends which enters the ground, or into soft or hard materials, as the screws turns in such direction that the front edge of the thread is forced into the ground. Such method of securement either fastens the anchor within the ground so that an article may utilize the fastening force of the anchor to hold the article in the ground, or the anchor may support an article above the ground. The present invention is particularly applicable to support umbrellas over the ground, although it will be appreciated that the invention could advantageously be used for other ground-anchoring or fastening functions, including supporting pipes and cables, and the like.
2. Description of the Related Art
Prior art screws generally have one continuous spiraling thread about the lower end to enter and embed within the ground. As such, each rotation of the screw only further inserts into the ground an additional small part of the spiraling thread. Even with narrow thread pitch, prior art screws must be repeatedly rotated in order to functionally secure or support an article. Without either a deep penetration into the material or a significant lateral extension of the thread, the prior art screw may slip in softer material, such as beach sand.
A typical prior art anchoring device is shown in U.S. Pat. No. 4,832,304, to Morgulis. Morgulis teaches a ground anchoring devices particularly for umbrellas, which has a spiraling thread for threading into the ground. However, Morgulis only teaches a single spirally threaded screw for fastening the umbrella into the ground, not a plurality of discontinuous ridges as does the present invention. The Morgulis anchoring device must therefore be driven deeply into the ground to withstand the force of wind buffeting the umbrella. Otherwise, given the surface area of a umbrella, such significant force may easily dislodge an umbrella from beach sand.
Another prior art anchor is demonstrated in U.S. Pat. No. 4,819,904 to Shpigel, et al. Shpigel teaches a conical anchor which, when embedded in the ground, has a screw thread which selectively extends from the surface of the anchor. Shpigel does not teach the use of a plurality of ridges to hold the anchor into the ground. The anchor device of Shpigel has a further problem in that it cannot easily extend its threading in dense material, as opposed to dirt or sand, as the material will resist the lateral pressure of the extension of the threading.